Make original_response_headers parameter of NetworkDelegate::OnHeadersReceived const

chrome/browser/net/chrome_network_delegate.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/net/chrome_network_delegate.h"
 
 #include "base/logging.h"
 #include "base/base_paths.h"
 #include "base/path_service.h"
 #include "chrome/browser/api/prefs/pref_member.h"
@@ skipping 224 matching lines @@
 void ChromeNetworkDelegate::OnSendHeaders(
     net::URLRequest* request,
     const net::HttpRequestHeaders& headers) {
   ExtensionWebRequestEventRouter::GetInstance()->OnSendHeaders(
       profile_, extension_info_map_.get(), request, headers);
 }
 
 int ChromeNetworkDelegate::OnHeadersReceived(
     net::URLRequest* request,
     const net::CompletionCallback& callback,
-    net::HttpResponseHeaders* original_response_headers,
+    const net::HttpResponseHeaders* original_response_headers,
     scoped_refptr<net::HttpResponseHeaders>* override_response_headers) {
   return ExtensionWebRequestEventRouter::GetInstance()->OnHeadersReceived(
       profile_, extension_info_map_.get(), request, callback,
       original_response_headers, override_response_headers);
 }
 
 void ChromeNetworkDelegate::OnBeforeRedirect(net::URLRequest* request,
                                              const GURL& new_location) {
   ExtensionWebRequestEventRouter::GetInstance()->OnBeforeRedirect(
       profile_, extension_info_map_.get(), request, new_location);
@@ skipping 193 matching lines @@
 #endif
   return net::OK;
 }
 
 void ChromeNetworkDelegate::OnRequestWaitStateChange(
     const net::URLRequest& request,
     RequestWaitState state) {
   if (load_time_stats_)
     load_time_stats_->OnRequestWaitStateChange(request, state);
 }